Study to Assess Safety, Tolerability, Pharmacokinetic & Pharmacodynamic Effect of UCB5857 in Healthy & Psoriatic Subject

This is a first-in-human (FIH), Phase 1, randomized, double-blind, placebo controlled, single center study designed to evaluate the safety/ tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of UCB5857 following oral administration of single ascending doses (SAD) in healthy subjects (Part 1) and multiple ascending doses (MAD) in healthy and mild-to-moderate psoriatic subjects (Part 2). The primary objective of this study is to investigate the safety and tolerability of UCB5857 when given as single oral doses in healthy subjects and as ascending multiple oral doses in healthy subjects and mild-to-moderate psoriatic subjects.